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PostPosted: 23 Jul 2009, 20:21 
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Joined: 06 Jun 2008, 14:03
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Location: Tulsa, Oklahoma
I am working on a pair of eico hf 60 amps and one is fine on the voltages the other is low on all voltages, I found in the schematic that on T1 is shows two line ins one for 115 and one for 135, the good one has the 115 wired to the power cord, the other has a red black wired to the power cord. but I don't see the other green black anywere. How would I bring up the b+ and filement voltages to the proper level?
Here is a link to the schematic.
http://www.triodeel.com/hf5060s.gif

any insight would be a lot of help, Thanks Steven A.


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PostPosted: 23 Jul 2009, 22:24 
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Location: Winnipeg, CANADA
Hi Steven, did you try swapping the rectifiers between the two units to rule out the tubes?

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PostPosted: 23 Jul 2009, 23:13 
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Location: Tulsa, Oklahoma
yes i did, All the voltages on the power tranny are low comard to the other one and the schematic, the 5 volt is around 3 volts and the filement is 4.3 with all tubes removed, on the good one there spot on. the only difference I see is on the good one is on the power tranny primary, it is useing the green/black on the schematic and the low one is useing the red/black but I don't see the green/black on the one I am haveing trouble with. It does play but is about 30% lower volume than the other one.
if I can find the other primary wire I would swap it to see if the voltages come up.
If I run the veriac upto 135 volts it reads fine on the voltages and sounds the same as the other one.


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PostPosted: 24 Jul 2009, 18:02 
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Joined: 08 May 2009, 08:20
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Location: Duesseldorf, Germany
Hey Steven, Hi Gio,

thats a bit confusing....
Quote:
the good one has the 115 wired to the power cord, the other has a red black wired to the power cord.

IMHO - the 115V primary are the RED / BLACK wires without the GRN / BLK connected..
If you have 115VAC MAINS, the tranny should (must) be connected to the RED / BLACK. That's on the schematic. The GRN / BLACK is optional for 132 VAC MAINS. If you have 115VAC MAINS and the amp is connected to GRN / BLACK (135V) the tranny has a lower voltage on the secondary winding (about 17-23%). That's accurate.

IMHO - I would go for trying to measure the resistance from both trannys, at the primary windings, at the 115V taps (RED / BLACK). If the resistance is more than 2-3% different to the other one, there surely is something wrong. The schematic says that RED / BLACK is for 115V MAINS - if the two amps are the same revision / series.
With RED / BLACK @ 115VAC MAINS you must have the higher and correct output on the secondary.
For the V-out measuring I would take the heater voltage as reference.

So - i'd first check out the resistance - compared to the good tranny - to be sure that there's no fault. Then check out all the leads from the tranny again, to be sure, what there's connected. Be sure how the mains wiring goes to the tranny and where it is connected. Maybe there is the fault. Maybe the trannys are not the same?

Some pics maybe could be useful to go further.

I'm 2 weeks offline now... :( Have fun!!

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Tom.

Some of my projects: TDA2050 Chip Amp, the LM3886 Gainclone Thread and the Szekeres Headamp Thread.


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PostPosted: 25 Jul 2009, 07:26 
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Joined: 14 Oct 2008, 17:35
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Location: Dartmouth, Nova Scotia
Does it look like anyone has tampered with this tranny? We would like to see some pictures as tombethe said if possible please. :geek: I still think you are lucky to have a stereo pair of Eico amplifiers, I have heard great things about them, so don't get rid of them! :up:

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PostPosted: 26 Jul 2009, 09:11 
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Location: Tulsa, Oklahoma
Well I opened up the said tranny looking for the other yap and there is none in it so the owner ordered a new tranny from hammond of the propper specs I wish I had a working camera but mine died or I would post some pics.
Wgen the part gets here I will install it and recheak everthing and post back,


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PostPosted: 26 Jul 2009, 22:12 
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Joined: 14 Oct 2008, 17:35
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Location: Dartmouth, Nova Scotia
Good job! :up: Hammond is great, as for the poor camera.... all you need to do is go to a pawn shop and buy a cheap used one, the one I use is a Canon PS530, case is beaten to heck and the lens shutter is broken, but it works wonders for taking good pictures of projects, and even has a macro setting for close ups. It is only 5MP and my old one was 4MP(PS520) but you could easily buy the same type for under $150 new and used maybe like $50-100, mine was from a friend for $60, and I bought it because it was the same as the PS520 but higher resolution. The old one I use as parts. :)

This has nothing to do with the thread but I really would like to see those amplifiers, and you may have noticed that most of my pictures are well taken, right Endspec. ;)

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PostPosted: 27 Jul 2009, 06:57 
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Location: Tulsa, Oklahoma
yup good pics, i will be getting a ca will see if the owner can snap a pic or two for me.


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PostPosted: 27 Jul 2009, 19:10 
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Joined: 06 Jun 2008, 14:03
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Location: Tulsa, Oklahoma
Well I repaird the tranny, the 115 volt tape was cut off inside the tranny so i solderd a lead on it and wired it up and the b+ and filements came up to specs and they sound = to each other and man they sound good, would love to hold on to them till the caps break in. There getting shipped back to the owner friday and he will polish them up and send me pics to post as few days after he gets them back.
Thanks for all the input on this
Steven A.


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PostPosted: 10 Aug 2009, 05:59 
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Joined: 08 May 2009, 08:20
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Location: Duesseldorf, Germany
Hi Steven, Hi all!

Back @ home now :-)

Nice job Steven - congrats!

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Tom.

Some of my projects: TDA2050 Chip Amp, the LM3886 Gainclone Thread and the Szekeres Headamp Thread.


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